i guesstamate the sump to be about 30 - 40 gallons. it's pretty big. I got the euroreef cs 6-2 skimmer in there, and my filter is one of those micro bags. none of those bio balls, and the return is gonna be a Mag950. Havent set it up yet, but will get everything up and goin hopefully tomorrow. Oh, and are there any thoughts on Oceanic salt, i heard that it's good but then my LFS says that it garbage. Instant Salt is what they recomend. What you all think?